58 



lection has in all cases been amply proved, because it has been found that 

 the selected areas contained representatives of practically all the tree 

 species that are found in Java. Occasionally, however, there will be 

 found outside the type areas a rare species or one of very local distribu- 

 tion that is not to be found'in any of the selected type areas. In another 

 manner the value of this method of studying the forest flora is shown, for 

 by the careful study of these type areas many tree species have been added 

 to the Java flora that were previously unknown to the Island, and in some 

 cases these species new to the flora are found to be of wide distribution 

 there. 



Since 1888 some twenty-seven of these type areas have boen selected 

 and carefully studied, many of them, especially those of the plain region, 

 containing several square miles each ; others, especially those on the high 

 mountains, being of comparatively small size. They are not reserved 

 from timber or agricultural exploitation, and occasionally it has happened 

 that where type areas were thickly forested eight or ten years ago, now all 

 of the original vegetation has been removed, and plantations of coffee, 

 tea, or tobacco arc found. It is not necessary to continue these extensive 

 observations for a long period of years on all these type areas, and accord- 

 ingly, after five, six or eight years, as the case may be, when all the in- 

 formation available or desired has been secured, the labels on the trees 

 are removed and the area is abandoned. 



To establish a basis for these investigations, Dr. Koorders divided Java 

 into three geographical divisions, East Java, Middle Java, and West Java, 

 each region characterized by extensive areas of country at a comparatively 

 low elevation above the sea and each containing high mountains approx- 

 imating 4,000 meters in altitude. Again, he arbitrarily divided the 

 Island into four altitudinal regions or sections, thus making in all twelve 

 botanical regions in the whole Island. The first of these altitudinal sec- 

 tions extends from the sea level to a height of 1,000 meters; the second 

 from 1,000 to 2,000 meters; the third from 2,000 to 3,000 meters, and the 

 fourth above 3,000 meters. In each of these altitudinal sections in East, 

 Middle, and West Java type areas were selected. In the first altitudinal 

 section — that is, from the sea level up to 1,000 meters — is of course to be 

 found not only the greatest suixtficial area but also the greatest number of 

 tree species, and acordingly in tlie first section, in East, Middle, and West 

 Java, were selected three or four type areas ; in the second altitudinal sec- 

 tion two or three type areas ; in the third one or two type areas, and in 

 the fourth but one small plot near the summit of some one of the higher 

 mountains in each of the three geographical regions. 



In the Island of Java there are about 1,400 tree species known, and of 

 these 1,400 species probably 1,200 attain a diameter of 12 centimeters or 

 more. As noted above, the preponderance of tree species is found at the 



